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Related papers: On weak greedy algorithms

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We consider the problem of sparse atomic optimization, where the notion of "sparsity" is generalized to meaning some linear combination of few atoms. The definition of atomic set is very broad; popular examples include the standard basis,…

Optimization and Control · Mathematics 2019-12-30 Thomas Zhang

This paper proposes a new algorithm for multiple sparse regression in high dimensions, where the task is to estimate the support and values of several (typically related) sparse vectors from a few noisy linear measurements. Our algorithm is…

Machine Learning · Statistics 2012-06-08 Ali Jalali , Sujay Sanghavi

Greedy algorithms have been successfully analyzed and applied in training neural networks for solving variational problems, ensuring guaranteed convergence orders. In this paper, we extend the analysis of the orthogonal greedy algorithm…

Numerical Analysis · Mathematics 2025-04-21 Jinchao Xu , Xiaofeng Xu

The problem of convex optimization is studied. Usually in convex optimization the minimization is over a d-dimensional domain. Very often the convergence rate of an optimization algorithm depends on the dimension d. The algorithms studied…

Machine Learning · Statistics 2015-11-05 Vladimir Temlyakov

We address the problem of minimizing a convex function over the space of large matrices with low rank. While this optimization problem is hard in general, we propose an efficient greedy algorithm and derive its formal approximation…

Machine Learning · Computer Science 2011-06-09 Shai Shalev-Shwartz , Alon Gonen , Ohad Shamir

The general theory of greedy approximation with respect to arbitrary dictionaries is well developed in the case of real Banach spaces. Recently, some of results proved for the Weak Chebyshev Greedy Algorithm (WCGA) in the case of real…

Functional Analysis · Mathematics 2024-10-01 A. Gasnikov , V. Temlyakov

In this paper we study greedy approximation in Banach spaces. We discuss a modification of the Weak Chebyshev Greedy Algorithm, in which steps of the algorithm can be executed imprecisely. Such inaccuracies are represented by both absolute…

Functional Analysis · Mathematics 2021-06-07 Anton Dereventsov

Submodular functions are well-studied in combinatorial optimization, game theory and economics. The natural diminishing returns property makes them suitable for many applications. We study an extension of monotone submodular functions,…

Discrete Mathematics · Computer Science 2014-11-18 Allan Borodin , Dai Tri Man Le , Yuli Ye

We connect high-dimensional subset selection and submodular maximization. Our results extend the work of Das and Kempe (2011) from the setting of linear regression to arbitrary objective functions. For greedy feature selection, this…

Machine Learning · Statistics 2017-10-13 Ethan R. Elenberg , Rajiv Khanna , Alexandros G. Dimakis , Sahand Negahban

This paper defines weak-$\alpha$-supermodularity for set functions. Many optimization objectives in machine learning and data mining seek to minimize such functions under cardinality constrains. We prove that such problems benefit from a…

Data Structures and Algorithms · Computer Science 2015-02-24 Christos Boutsidis , Edo Liberty , Maxim Sviridenko

Submodular functions are a broad class of set functions, which naturally arise in diverse areas. Many algorithms have been suggested for the maximization of these functions. Unfortunately, once the function deviates from submodularity, the…

Discrete Mathematics · Computer Science 2017-07-17 Lin Chen , Moran Feldman , Amin Karbasi

We define and study greedy matchings in vertex-ordered bipartite graphs. It is shown that each vertex-ordered bipartite graph has a unique greedy matching. The proof uses (a weak form of) Newman's lemma. The vertex ordering is called a…

Discrete Mathematics · Computer Science 2024-02-13 Hans U. Simon

We perform an experimental study of algorithms for online bipartite matching under the known i.i.d. input model with integral types. In the last decade, there has been substantial effort in designing complex algorithms with the goal of…

Data Structures and Algorithms · Computer Science 2018-08-16 Allan Borodin , Christodoulos Karavasilis , Denis Pankratov

We analyze the orthogonal greedy algorithm when applied to dictionaries $\mathbb{D}$ whose convex hull has small entropy. We show that if the metric entropy of the convex hull of $\mathbb{D}$ decays at a rate of $O(n^{-\frac{1}{2}-\alpha})$…

Statistics Theory · Mathematics 2022-01-25 Jonathan W. Siegel , Jinchao Xu

Motivated by recent work on stochastic gradient descent methods, we develop two stochastic variants of greedy algorithms for possibly non-convex optimization problems with sparsity constraints. We prove linear convergence in expectation to…

Numerical Analysis · Mathematics 2014-07-02 Nam Nguyen , Deanna Needell , Tina Woolf

This paper describes a simple greedy D-approximation algorithm for any covering problem whose objective function is submodular and non-decreasing, and whose feasible region can be expressed as the intersection of arbitrary (closed upwards)…

Data Structures and Algorithms · Computer Science 2015-06-02 Christos Koufogiannakis , Neal E. Young

In [25], T. Oikhberg introduced and studied variants of the greedy and weak greedy algorithms for sequences with gaps, with a focus on the $\mathbf n$-$t$-quasi-greedy property that is based on them. Building upon this foundation, our…

Functional Analysis · Mathematics 2023-09-04 Miguel Berasategui , Pablo M. Berná

For compressed sensing over arbitrarily connected networks, we consider the problem of estimating underlying sparse signals in a distributed manner. We introduce a new signal model that helps to describe inter-signal correlation among…

Information Theory · Computer Science 2013-10-29 Dennis Sundman , Saikat Chatterjee , Mikael Skoglund

Collective communications are ubiquitous in parallel applications. We present two new algorithms for performing a reduction. The operation associated with our reduction needs to be associative and commutative. The two algorithms are…

Distributed, Parallel, and Cluster Computing · Computer Science 2013-10-18 Bradley R. Lowery , Julien Langou

The first aim of this paper is to establish the weak convergence rate of nonlinear two-time-scale stochastic approximation algorithms. Its second aim is to introduce the averaging principle in the context of two-time-scale stochastic…

Probability · Mathematics 2007-05-23 Abdelkader Mokkadem , Mariane Pelletier